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多晶硅 2

700 m跨径级别 1

B级钢 1

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CP）；符号间干扰（inter symbol interference， ISI）；载波间干扰（inter carrier interference 1

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Grade 91钢 1

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Ascalable and efficient IPv4 address sharing approach in IPv6 transition scenarios

Guo-liang HAN,Cong-xiao BAO,Xing LI

《信息与电子工程前沿（英文）》 2015年 第16卷 第8期   页码 634-645 doi: 10.1631/FITEE.1500022

摘要： IPv6 has been an inevitable trend with the depletion of the global IPv4 address space. However, new IPv6 users still need public IPv4 addresses to access global IPv4 users/resources, making it important for providers to share scarce global IPv4 addresses effectively. There are two categories of solutions to the problem, carrier-grade NAT (CGN) and ‘A+P’ (each customer sharing the same IPv4 address is assigned an excluded port range). However, both of them have limitations. Specifically, CGN solutions are not scalable and can bring much complexity in managing customers in large-scale deployments, while A+P solutions are not flexible enough to meet dynamic port requirements. In this paper, we propose a hybrid mechanism to improve current solutions and have deployed it in the Tsinghua University Campus Network. The real traffic data shows that our mechanism can utilize limited IPv4 addresses efficiently without degrading the performance of applications on end hosts. Based on the enhanced mechanism, we propose a method to help service providers make address plans based on their own traffic patterns and actual requirements.

关键词： IPv6 transition     Carrier-grade NAT (CGN)     A+P     Address sharing     Dynamic switching    

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Application of Grading of Recommendations Assessment, Development, and Evaluation (GRADE) to the guideline

null

《医学前沿（英文）》 2017年 第11卷 第4期   页码 590-594 doi: 10.1007/s11684-017-0537-4

摘要：

Grading of Recommendations Assessment, Development, and Evaluation (GRADE) offers a worldwide approach to guideline development for clinical practice. For the clinical practice of acupuncture therapy, 18 evidence-based guidelines have been developed in China using GRADE. In this study, we review the advantages and limitations of the GRADE approach in the guideline development for acupuncture and moxibustion and propose some solutions to these limitations. Scientific advantages of rating the quality of evidence, outcome-centric direction, overall progression to develop recommendations, and strength of recommendations providing specific clinical guidance are the advantages of GRADE. The limitations of GRADE in the development of guidelines for acupuncture and moxibustion include rating the quality of evidence for ancient literature and literature on famous traditional Chinese medicine experts’ experiences and specific guidelines for formulating recommendations from evidence. In the guideline development for clinical practice with acupuncture and moxibustion, we suggest that a specific method should be explored based on the GRADE approach and the characteristics of acupuncture therapy.

关键词： guideline     acupuncture     GRADE    

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Development of combined transitional pavement structure for urban tram track-road grade crossings

《结构与土木工程前沿（英文）》   页码 1199-1210 doi: 10.1007/s11709-023-0949-y

摘要： The grade crossings and adjacent pavements of urban trams are generally subjected to complex load conditions and are susceptible to damage. Therefore, in this study, a novel pavement structure between tram tracks and roads constructed using polyurethane (PU) elastic concrete and ultra-high-performance concrete (UHPC), referred to as a track-road transitional pavement (TRTP), is proposed. Subsequently, its performance and feasibility are evaluated using experimental and numerical methods. First, the mechanical properties of the PU elastic concrete are evaluated. The performance of the proposed structure is investigated using a three-dimensional finite element model, where vehicle-induced dynamic and static loads are considered. The results show that PU elastic concrete and the proposed combined TRTP are applicable and functioned as intended. Additionally, the PU elastic concrete achieved sufficient performance. The recommended width of the TRTP is approximately 50 mm. Meanwhile, the application of UHPC under a PU elastic concrete layer significantly reduces vertical deformation. Results of numerical calculations confirmed the high structural performance and feasibility of the proposed TRTP. Finally, material performance standards are recommended to provide guidance for pavement design and the construction of tram-grade crossings in the future.

关键词： urban tram track     grade crossing     combined track-road transitional pavement     polyurethane elastic concrete     finite element method    

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Visible-light-driven heterostructured g-CN/Bi-TiO floating photocatalyst with enhanced charge carrier

《环境科学与工程前沿（英文）》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1417-3

摘要：

• Bi doping in TiO2 enhanced the separation of photo-generated electron-hole.

关键词： Bi doping     Visible light     Algal removal     Charge carrier separation    

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Triage for management of cervical high-grade squamous intraepithelial lesion patients with positive margin

null

《医学前沿（英文）》 2017年 第11卷 第2期   页码 223-228 doi: 10.1007/s11684-017-0517-8

摘要：

The objective of this study is to guide a triage for the management of cervical high-grade squamous intraepithelial lesion (HSIL) patients with positive margin by conization. Clinico-pathological data of HSIL patients with positive margin by conization were retrospectively collected from January 2009 to December 2014. All patients underwent secondary conization or hysterectomy within 6 months. The rate of residual lesion was calculated, and the factors associated with residual lesion were analyzed by univariate and multivariate analyses. Among a total of 119 patients, 56 (47.06%) patients presented residual HSIL in their subsequent surgical specimens, including 4 cases of invasive cervical carcinoma (3 stage IA1 and 1 stage IA2 patients). Univariate analysis showed that patient age>35 years (P=0.005), menopausal period>5 years (P=0.0035), and multiple-quadrant involvement (P=0.001) were significantly correlated with residual disease; however, multivariate analysis revealed that multiple-quadrant involvement (P=0.001; OR, 3.701; 95%CI, 1.496–9.154) was an independent risk factor for residual disease. Nearly half of HSIL patients with positive margin by conization were disease-free in subsequent surgical specimens, and those with multiple positive margins may consider re-conization or re-assessment.

关键词： cervical high-grade squamous intraepithelial lesion     conization     positive surgical margin     hysterectomy    

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Charge-carrier photogeneration and extraction dynamics of polymer solar cells probed by a transient photocurrent

Boa Jin, Hyunmin Park, Yang Liu, Leijing Liu, Jongdeok An, Wenjing Tian, Chan Im

《化学科学与工程前沿（英文）》 2021年 第15卷 第1期   页码 164-179 doi: 10.1007/s11705-020-1976-z

摘要： To understand the complex behaviors of photogenerated charge carriers within polymer-based bulk-heterojunction-type solar cells, the charge-carrier photogeneration and extraction dynamics are simultaneously estimated using a transient photocurrent technique under various external-bias voltages, and a wide range of excitation intensities are analyzed. For this purpose, conventional devices with 80 nm thick active layers consisting of a blend of representative P3HT and PTB7 electron-donating polymers and proper electron-accepting fullerene derivatives were used. After the correction for the saturation behavior at a high excitation-intensity range nearby the regime of the space charge-limited current, the incident-photon-density-dependent maximum photocurrent densities at the initial peaks are discussed as the proportional measures of the charge-carrier-photogeneration facility. By comparing the total number of the extracted charge carriers to the total number of the incident photons and the number of the initially photogenerated charge carriers, the external quantum efficiencies as well as the extraction quantum efficiencies of the charge-carrier collection during a laser-pulse-induced transient photocurrent process were obtained. Subsequently, the charge-carrier concentration-dependent mobility values were obtained, and they are discussed in consideration of the additional influences of the charge-carrier losses from the device during the charge-carrier extraction that also affects the photocurrent-trace shape.

关键词： charge-carrier photogeneration     transient photocurrent     polymer solar cells     charge-carrier extraction     space charge-limited current    

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Grade 91钢抗蠕变性能的计算热力学研究 Article

Andrew Smith, Mohammad Asadikiya, Mei Yang, Jiuhua Chen, Yu Zhong

《工程（英文）》 2020年 第6卷 第6期   页码 644-652 doi: 10.1016/j.eng.2019.12.004

摘要：

本研究旨在了解在焊接Grade 91（Gr.91）钢时，热影响区（HAZ）内不同的临界温度与第二相的稳定性之间的关系。IV型开裂出现在Gr.91钢的焊接热影响区。

关键词： Grade 91钢     抗蠕变性能     铁素体-马素体钢     焊缝组织     计算热力学     第二相     合金成分    

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基于PFM的B级钢侧架耐久性分析

李伟,李强,王平

《中国工程科学》 2011年 第13卷 第1期   页码 56-61

摘要：

基于概率断裂力学对B级钢货车侧架的圆角细节进行了模拟耐久性试验研究，提出了一种新的通用当量初始缺陷尺寸分布的计算方法，建立了裂纹超越概率模型，从存活概率P, 应力水平σ, 裂纹形成时间t和经济维修极限ae 4个角度评估了结构的损伤度, 并结合实测的应力谱预测了其经济寿命。结果表明，裂纹萌生时间能很好地服从三参数Weibull分布，求得的通用EIFS分布参数通过了K—S检验，拟合效果很好。裂纹超越概率模型可以对结构产生的耐久性损伤进行定量度量，预测的经济寿命随裂纹穿越概率的增加呈现增长的趋势，验证了新的计算方法和概率模型的合理有效性。

关键词： 耐久性     疲劳     B级钢     裂纹    

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Multi-objective genetic algorithms based structural optimization and experimental investigation of the planet carrier

Pengxing YI,Lijian DONG,Tielin SHI

《机械工程前沿（英文）》 2014年 第9卷 第4期   页码 354-367 doi: 10.1007/s11465-014-0319-5

摘要：

To improve the dynamic performance and reduce the weight of the planet carrier in wind turbine gearbox, a multi-objective optimization method, which is driven by the maximum deformation, the maximum stress and the minimum mass of the studied part, is proposed by combining the response surface method and genetic algorithms in this paper. Firstly, the design points’ distribution for the design variables of the planet carrier is established with the central composite design (CCD) method. Then, based on the computing results of finite element analysis (FEA), the response surface analysis is conducted to find out the proper sets of design variable values. And a multi-objective genetic algorithm (MOGA) is applied to determine the direction of optimization. As well, this method is applied to design and optimize the planet carrier in a 1.5 MW wind turbine gearbox, the results of which are validated by an experimental modal test. Compared with the original design, the mass and the stress of the optimized planet carrier are respectively reduced by 9.3% and 40%. Consequently, the cost of planet carrier is greatly reduced and its stability is also improved.

关键词： planet carrier     multi-objective optimization     genetic algorithms     wind turbine gearbox     modal experiment    

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Silver-catalyzed bioleaching for raw low-grade copper sulphide ores

Tianlong DENG, Yafei GUO, Mengxia LIAO, Dongchan LI

《化学科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 250-254 doi: 10.1007/s11705-009-0049-0

摘要： This research was conducted to investigate the biooxidation and copper dissolution from raw low-grade refractory copper sulphide ores located in the Xinjiang Autonomous Region of China using adapted bacteria. In order to accelerate the bioleaching rate, the adapted mixed bacteria and silver ion catalyst were tested in the leach columns at laboratory scale. The overall acid consumption was 4.3 kg sulphuric acid per kg of dissolved copper and was linearly related to the percent copper dissolution. The calculated copper dissolution rates obey the Shrinking Core Model. The relative activation energy of the whole biooxidative leaching stages was calculated to be 48.58 kJ/mol.

关键词： green process     biohydrometallurgy     bioleaching     reaction kinetics     sulphide ores    

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基于五品联动理论的品位效益优化决策研究

邵安林

《中国工程科学》 2014年 第16卷 第2期   页码 68-72

摘要：

本文以五品联动理论为研究背景，考虑到矿山工程中地质工程、采矿工程、配矿工程、选矿工程和冶炼工程5 个工程是相互联系的串联耦合工程，是矿山企业活动的主体，而与其相对应的地质品位、采出品位、入选品位、精矿品位和入炉品位对于矿山整体经济效益起到关键的控制作用。本文运用并拓展了“质量守恒”原理，利用“矿量守恒”和“金属量守恒”建立了品位经济效益模型，提出了五品联动品位—效益活跃指数，通过实例计算与分析，获得了某铁矿的品位优化数值，为进一步研究矿山企业工程管理模式奠定了基础。

关键词： 五品联动     品位—效益活跃指数     优化决策     矿冶工程    

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Effects of carrier-attached biofilm on oxygen transfer efficiency in a moving bed biofilm reactor

Yanling WEI,Xunfei YIN,Lu QI,Hongchen WANG,Yiwei GONG,Yaqian LUO

《环境科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 569-577 doi: 10.1007/s11783-015-0822-x

摘要： Three laboratory-scale moving bed biofilm reactors (MBBR) with different carrier filling ratios ranging from 40% to 60% were used to study the effects of carrier-attached biofilm on oxygen transfer efficiency. In this study, we evaluated the performance of three MBBRs in degrading chemical oxygen demand and ammonia. The three reactors removed more than 95% of -N at an air flow-rate of 60 L·h . The standard oxygen transfer efficiency (αSOTE) of the three reactors was also investigated at air flow-rates ranging from 60 to 100 L·h . These results were compared to αSOTE of wastewater with a clean carrier (no biofilm attached). Results showed that under these process conditions, αSOTE decreased by approximately 70% as compared to αSOTE of wastewater at a different carrier-filling ratio. This indicated that the biofilm attached to the carrier had a negative effect on αSOTE. Mechanism analysis showed that the main inhibiting effects were related to biofilm flocculants and soluble microbial product (SMP). Biofilm flocs could decrease αSOTE by about 20%, and SMP could decrease αSOTE by 30%–50%.

关键词： carrier     biofilm     oxygen transfer efficiency     moving bed biofilm reactor    

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Effects of BTA2 as the third component on the charge carrier generation and recombination behavior of

Leijing Liu, Hao Zhang, Bo Xiao, Yang Liu, Bin Xu, Chen Wang, Shanpeng Wen, Erjun Zhou, Gang Chen, Chan Im, Wenjing Tian

《化学科学与工程前沿（英文）》 2021年 第15卷 第1期   页码 127-137 doi: 10.1007/s11705-020-1936-7

摘要： Effects of a benzotriazole (BTA)-based small molecule, BTA2, as the third component on the charge carrier generation and recombination behavior of poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7):[6,6]-phenyl-C -butyric acid methyl ester (PC BM) organic solar cells (OSCs) were investigated by optical simulation of a transfer matrix model (TMM), photo-induced charge extraction by linearly increasing voltage (photo-CELIV) technique, atomic force microscope (AFM), and the Onsager–Braun model analysis. BTA2 is an A A D A A -type non-fullerene small molecule with thiazolidine-2,4-dione, BTA, and indacenodithiophene as the terminal acceptor (A ), bridge acceptor (A ), and central donor (D), respectively. The short-circuit current density of the OSCs with BTA2 can be enhanced significantly owing to a complementary absorption spectrum. The optical simulation of TMM shows that the ternary OSCs exhibit higher internal absorption than the traditional binary OSCs without BTA2, resulting in more photogenerated excitons in the ternary OSCs. The photo-CELIV investigation indicates that the ternary OSCs suffer higher charge trap-limited bimolecular recombination than the binary OSCs. AFM images show that BTA2 aggravates the phase separation between the donor and the acceptor, which is disadvantageous to charge carrier transport. The Onsager-Braun model analysis confirms that despite the charge collection efficiency of the ternary OSCs being lower than that of the binary OSCs, the optimized photon absorption and exciton generation processes of the ternary OSCs achieve an increase in photogenerated current and thus improve power conversion efficiency.

关键词： third component     organic solar cells     charge carrier generation     charge carrier recombination     bimolecular recombination    

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Nitrogen removal efficiencies and microbial communities in full-scale IFAS and MBBR municipal wastewater treatment plants at high COD:N ratio

Supaporn Phanwilai, Naluporn Kangwannarakul, Pongsak (Lek) Noophan, Tamao Kasahara, Akihiko Terada, Junko Munakata-Marr, Linda Ann Figueroa

《环境科学与工程前沿（英文）》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1374-2

摘要： Abstract • Two IFAS and two MBBR full-scale systems (high COD:N ratio 8:1) were characterized. • High specific surface area carriers grew and retained slow-growing nitrifiers. • High TN removal is related to high SRT and low DO concentration in anoxic tanks. The relative locations of AOB, NOB, and DNB were examined for three different kinds of carriers in two types of hybrid biofilm process configurations: integrated fixed-film activated sludge (IFAS) and moving bed biofilm reactor (MBBR) processes. IFAS water resource recovery facilities (WRRFs) used AnodkalnessTM K1 carriers (KC) at Broomfield, Colorado, USA and polypropylene resin carriers (RC) at Fukuoka, Japan, while MBBR WRRFs used KC carriers at South Adams County, Colorado, USA and sponge carriers (SC) at Saga, Japan. Influent COD to N ratios ranged from 8:1 to 15:1. The COD and BOD removal efficiencies were high (96%–98%); NH4+-N and TN removal efficiencies were more varied at 72%–98% and 64%–77%, respectively. The extent of TN removal was higher at high SRT, high COD:N ratio and low DO concentration in the anoxic tank. In IFAS, RC with high specific surface area (SSA) maintained higher AOB population than KC. Sponge carriers with high SSA maintained higher overall bacteria population than KC in MBBR systems. However, the DNB were not more abundant in high SSA carriers. The diversity of AOB, NOB, and DNB was fairly similar in different carriers. Nitrosomonas sp. dominated over Nitrosospira sp. while denitrifying bacteria included Rhodobacter sp., Sulfuritalea sp., Rubrivivax sp., Paracoccus sp., and Pseudomonas sp. The results from this work suggest that high SRT, high COD:N ratio, low DO concentration in anoxic tanks, and carriers with greater surface area may be recommended for high COD, BOD and TN removal in WRRFs with IFAS and MBBR systems.

关键词： IFAS     MBBR     AnodkalnessTM K1 carrier     Polypropylene resin carrier     Sponge carrier    

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Reduction kinetics of SrFeO/CaO∙MnO nanocomposite as effective oxygen carrier for chemical looping partial

《化学科学与工程前沿（英文）》 2022年 第16卷 第12期   页码 1726-1734 doi: 10.1007/s11705-022-2188-5

摘要： Chemical looping reforming of methane is a novel and effective approach to convert methane to syngas, in which oxygen transfer is achieved by a redox material. Although lots of efforts have been made to develop high-performance redox materials, a few studies have focused on the redox kinetics. In this work, the kinetics of SrFeO3−δ–CaO∙MnO nanocomposite reduction by methane was investigated both on a thermo-gravimetric analyzer and in a packed-bed microreactor. During the methane reduction, combustion occurs before the partial oxidation and there exists a transition between them. The weight loss due to combustion increases, but the transition region becomes less inconspicuous as the reduction temperature increased. The weight loss associated with the partial oxidation is much larger than that with combustion. The rate of weight loss related to the partial oxidation is well fitted by the Avrami–Erofeyev equation with n = 3 (A3 model) with an activation energy of 59.8 kJ∙mol‒1. The rate law for the partial oxidation includes a solid conversion term whose expression is given by the A3 model and a methane pressure-dependent term represented by a power law. The partial oxidation is half order with respect to methane pressure. The proposed rate law could well predict the reduction kinetics; thus, it may be used to design and/or analyze a chemical looping reforming reactor.

关键词： chemical looping reforming     SrFeO3−δ/CaO·MnO nanocomposite     reduction kinetics     Avrami–Erofeyev model     pressure-dependent term    

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标题 作者 时间 类型 操作

Ascalable and efficient IPv4 address sharing approach in IPv6 transition scenarios

Guo-liang HAN,Cong-xiao BAO,Xing LI

期刊论文

Application of Grading of Recommendations Assessment, Development, and Evaluation (GRADE) to the guideline

null

期刊论文

Development of combined transitional pavement structure for urban tram track-road grade crossings

期刊论文

Visible-light-driven heterostructured g-CN/Bi-TiO floating photocatalyst with enhanced charge carrier

期刊论文

Triage for management of cervical high-grade squamous intraepithelial lesion patients with positive margin

null

期刊论文

Charge-carrier photogeneration and extraction dynamics of polymer solar cells probed by a transient photocurrent

Boa Jin, Hyunmin Park, Yang Liu, Leijing Liu, Jongdeok An, Wenjing Tian, Chan Im

期刊论文

Grade 91钢抗蠕变性能的计算热力学研究

Andrew Smith, Mohammad Asadikiya, Mei Yang, Jiuhua Chen, Yu Zhong

期刊论文

基于PFM的B级钢侧架耐久性分析

李伟,李强,王平

期刊论文

Multi-objective genetic algorithms based structural optimization and experimental investigation of the planet carrier

Pengxing YI,Lijian DONG,Tielin SHI

期刊论文

Silver-catalyzed bioleaching for raw low-grade copper sulphide ores

Tianlong DENG, Yafei GUO, Mengxia LIAO, Dongchan LI

期刊论文

基于五品联动理论的品位效益优化决策研究

邵安林

期刊论文

Effects of carrier-attached biofilm on oxygen transfer efficiency in a moving bed biofilm reactor

Yanling WEI,Xunfei YIN,Lu QI,Hongchen WANG,Yiwei GONG,Yaqian LUO

期刊论文

Effects of BTA2 as the third component on the charge carrier generation and recombination behavior of

Leijing Liu, Hao Zhang, Bo Xiao, Yang Liu, Bin Xu, Chen Wang, Shanpeng Wen, Erjun Zhou, Gang Chen, Chan Im, Wenjing Tian

期刊论文

Nitrogen removal efficiencies and microbial communities in full-scale IFAS and MBBR municipal wastewater treatment plants at high COD:N ratio

Supaporn Phanwilai, Naluporn Kangwannarakul, Pongsak (Lek) Noophan, Tamao Kasahara, Akihiko Terada, Junko Munakata-Marr, Linda Ann Figueroa

期刊论文

Reduction kinetics of SrFeO/CaO∙MnO nanocomposite as effective oxygen carrier for chemical looping partial

期刊论文